When you purchase a bandwidth plan, your upload and download connections are not necessarily symmetrical. If your upload connection is small, you might experience slow uploads to TelVue Connect. With large files, you are better off with a wired, not wireless, connection.
Find out your Internet bandwidth at Speakeasy Speedtest or Speedtest.net. Another cause of uploading problems could be packet loss. You can test how clean your connection is with free diagnotic tools such as WinMTR.net. Ultimately, if you truly want the fastest workflow, purchase as much Internet bandwidth as you can.